rkhunter complaining about /etc/passwd?

Tell rkhunter to ignore /etc/passwd by inserting EXISTWHITELIST="/etc/passwd" in your rkhunter configuration file. If you prefer not to make this change to your configuration file, make sure you run rkhunter --propupd with the same PATH as given in /etc/crontab. A command like

env -i PATH=/etc:/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin rkhunter --propupd

should suffice. Thanks to Mr. Torfinn Ingolfsen for his effort to track down this problem.